Re: [PATCH] fstests: generic test for fsync after fallocate

[Dave Chinner <david@fromorbit.com>]

On Mon, Apr 09, 2018 at 11:00:52AM +0100, Filipe Manana wrote:
> On Mon, Apr 9, 2018 at 10:51 AM, Dave Chinner <david@fromorbit.com> wrote:
> > On Sun, Apr 08, 2018 at 10:07:54AM +0800, Eryu Guan wrote:
> >> On Thu, Apr 05, 2018 at 10:56:14PM +0100, fdmanana@kernel.org wrote:
> > You also cannot assume that two separate preallocations beyond EOF
> > are going to be contiguous (i.e. it could be two separate extents.
> 
> I really don't care about that.
> Just want to check that allocated space is not lost, don't care if
> that space is covered by 1, 2 or more extents, or whether they are
> contiguous or not.

Sure, but that's not what the test does :/

> > What you should just be checking is that there are extents allocated
> > covering EOF to 3MB, not the exactly size, shape and type of extents
> > are allocated.
> 
> How to do such check, for a generic test, without using fiemap?

We already do such checks using fiemap, yes?

i.e. there's a bunch of _filter*fiemap() functions in common/punch
which should show you exactly how to do this i.e. filter all the
unwritten/data extents to be the same name, then they coalesce into
single ranges....

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com